Selectable: add ui-selectee class to elements matching filter on refresh. Fixes #7716 - Selectable: new elements added programatically don't have class ui-selectee

(cherry picked from commit 97bc2d9)

Author: rdworth

ui/jquery.ui.selectable.js

@@ -33,6 +33,7 @@ $.widget("ui.selectable", $.ui.mouse, {
 		var selectees;
 		this.refresh = function() {
 			selectees = $(self.options.filter, self.element[0]);
+			selectees.addClass("ui-selectee");
 			selectees.each(function() {
 				var $this = $(this);
 				var pos = $this.offset();